MCP MySQL Server

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description must fully disclose behavioral traits. It states the tool executes queries but fails to mention critical details like whether it requires authentication, what happens on success/failure (e.g., returns affected rows or error messages), or potential side effects (e.g., data modification). This leaves significant gaps in understanding the tool's behavior.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, direct sentence that efficiently conveys the core action without unnecessary words. It is front-loaded with the essential information ('Execute an INSERT, UPDATE, or DELETE query'), making it highly concise and well-structured for quick comprehension.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of a database mutation tool with no annotations and no output schema, the description is insufficient. It lacks details on behavioral aspects (e.g., error handling, return values), usage context (e.g., when to use vs. siblings), and does not explain what happens after execution. For a tool that modifies data, this leaves critical gaps in understanding.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, clearly documenting both parameters ('sql' and optional 'params'). The description adds no additional semantic information beyond what the schema provides, such as query format examples or parameter binding specifics. With high schema coverage, the baseline score of 3 is appropriate, as the description does not compensate but also does not detract.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'execute' and specifies the resource as 'INSERT, UPDATE, or DELETE query', making the purpose explicit. However, it does not differentiate from sibling tools like 'query' (which likely handles SELECT queries), leaving room for improvement in distinguishing its specific scope.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It does not mention when to use 'execute' over 'query' (for SELECT) or other siblings like 'create_table', nor does it specify prerequisites such as database connection requirements. This lack of context leaves the agent without clear usage instructions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.